An air flow rate measurement device to measure an inhaled air volume of an engine, to which a temperature sensor is attached, has heretofore been known. For example, an air flow rate measurement device described in Patent Document 1 has a temperature sensor to detect an air temperature outside a chassis including a flow rate sensor. A thermistor is used as the temperature sensor for example and two lead wires of the thermistor are extracted toward the side of a cover through a through-hole formed at a mount part of a chassis and electrically connected to terminals inserted into the cover. Here, the cover is secondarily formed over the mount part of the chassis.